The User Management function inside cPanel gives you the ability to create subaccounts with services such as email, FTP, and Web Disk access.
Subaccount
It is important to understand that this function does not allow you to create new cPanel accounts. It creates subaccounts for your account only.
Email:
When creating a subaccount, you may also create an email account associated with it. Alternatively, you can specify an external email address such as Gmail to be used in place of creating one.
FTP:
An FTP account allows the subaccount to manage the website files. The FTP username and password is the same as the username and password set for the account when it was created. Also in this option you can specify the top level directory which the account has access to. If you want them to only have access to the website files, use ‘public_html’.
Web Disk:
The Web Disk account allows the subaccount to manipulate files in the cPanel account on different interfaces such as a computer and mobile device. cPanel has a Web Disk Mobile App for iOS and Android.
Video Explanation